AJZ- If you trying to decide between 6.1 and 7.1, do a little searching here in the 950 saloon.

I put forth, that if you have the money and the space, there really aren't any reasons to do 6.1 vs 7.1. Dual rears gives a more solid soundstage in the rear of the room, helps to minimze the psycho-acoustical effect of reversal, and one of the best DSP algorythms for multichannel music and film, Logic 7, does not even offer 6.1 support. THX Ultra2 also recommends two rear speakers. I had 5.1 for years, 6.1 for 18 months, and 7.1 for about 6 months now. I much prefer my system with 7.1.